Odograph



1 KAMBQ oDoGRAPH May 7, 1929.

Filed May 5, 1.1927 2 Sheets-Sheet l aryl` 5 ffl" L. KAMBO oDoGRAPH May7, 1929.

Patented May 7, 1929. i i )l i ,UNITED STATES PATENT OFFICE;

LUIGI KAMBO, l' ROME, ITALY.

ODOGBAPH.

Application filed May 5, 1927, Serial No. 189,000, and in Italy May 10,1926.

The object ofthe invention is an odograph will have completed the arcMN, We shall i that is a device intended to trace automatihave alsocally, at a given scale, the course followed by any vehicle travellingon land, at sea, or (2) SIL-Rm in the air. Y S2=Rw2 In the annexeddra'wmg: and calling ws, m6, the corresponding rotations Flgure? l and 3Show. respectively a dm of the wheels 5 5 we shall have grammatie view,a topview and a slde elevation of a tricycle provided with a devicew1=7cw5 according to the invention; (3) w :kw

Figures 4 and 5 are two views of the dif- 2 ferential gear and speedchanging device of The Wheels 5,5' are keyd uPOnfhe en ds -the Odograph;of a divided axle 6,6 which carries at lts Figures 6 and 7 are geometricdiagrams: Gente? a C OflPlete dlffelentll gell' 7 WhOSG and satelllteplnlon 8,8 (Fig. 4,5) rotate respec- Figure 8 shows the' drawing sheetupon tlVely 11k@ the Wheels 5,5, which lthe course followed by thevehicle is If We Call Q the I`V0111t1011 0f the Satellites recorded.crown 9 around the axle 6,6 and p the rota- A Figures 1, 23nd 3 Show avehicle, for intion of the satellites 10,10 around their own Stance atrcycle whose Wheels arg1, 1 and axle, we shall have for the property ofthe 2; the distance between the centers of the dlflelentlal gear wheelsl and l is 2* and their radius R;

the wheels l and l are arallel and mounted A (4) (Ew-"L" loose on theiraxle spindles, they are connect- 2 25 ed with the two chain-wheels 3.3whose ra- =w5w6 dius is r; these chain-wheels drive by means i (5) T- ofthe two chains 4.4: the two chain-wheels 5'5 Whose radlus '1S T lt'bemgequations (2) an (3)v weshall have When the vehicle follows a circularpath S MN with the center at O and whose de- (7) so: K2

veloped length is S (Fig. 1), whose radius is p and which extends for anangle a, we then But-lv from the (l) We have have the relation If S1 isthe length of the arc described by S S 40 the outer wheel and S2, thelength of the' are (9) =ba described by the inner wheel, the relation isevidently and finally f we call m1, o2, the angles of rotation ofI R, K,b, being known constants we shall have the wheels 1, 1 their axles whenthe vehicle that By substitutin the values given by the 7 (a) therevolution Q of the satellites. crown is proportional to the circulararc followed by the vehicle (b) the rotation p of the satellites isproportional to the central angle of the circular arc followed by thevehicle.

This is true only for finite circular arcs but since we canconsider anycurve as formed by a succession of infinitesimal circular arcs, we shallhave for each of these In these formulas the variable radius hasdisappeared and they can be integrated, thus obtaining again theformulas (10) (11) and therefore, whatever be the shape of thetrajectory, the revolution will be proportional to the length of theroute followed by the Vehicle, and the rotation will be proportional tothe angular deviation of the axis of the vehicle from its initialdirection, since these deviation are equal to the sum of the centralangles of the infinitesimal arcs.

Therefore the differential records the two magnitudes Q and qi whichindividuate the movementof the 1vehicle namely the length S of thespace-covered and the deviation a from the initial direction.

It is necessary now to separate the rotation (p from the revolution Qwhich are amalgamated in the movement of the satellites.

Connected with the satellites 10,10 are two small gears 11,11 whichnaturally rotate by the same angle p; they mesh with the two racks 12,12which connect the two domeshaped pieces 13,13; these can run smoothlyalong the shaft 6,6. The conical pinions 10,10 and the small gears 11,11turn around axles supported by the hub 14, which connects the twoextremities of the divided axle 6,6', and by the satellites crown 9.

While the wheels 11,11 rotate bythe same angle (p, the racks 12,12 moveaccordingly away. driving the carriage 13,13 to the right or to the leftaccording as the center of the curve followed by the vehicle is to theright or to the left of its path.

Above the carriage 13,13 is provided a rack bar 15 having teeth in itsupper face and which moves in a straight line; andbears at both its endstwo rollers 16,16 which transfer to the bar 15, the carriage translationwhlch is proportional to the angle a.

Summing up, the bar 15 will move olf in proportion to the angles a andthe satellites crown 9 will rotate by the angle Q-which is proportionalto length S of the path covered. Thus the two elements of the movementof the vehicle have beenseparated.

The crown 9 by means of a transmission (a chain, for instance),communicates its movement tog the axle 17 which carries the twosprocketl wheels 18,18 provided with projecting pins; it is evident thatthese two wheels move with a speed proportional to that of thesatellites crown and consequently `is referred the course of thevehicle; thisv result may be obtained by means of the gradual speedchanging device (Figs. 4-5) Two circular supports 19,20, secured to aplatform 21, carry a hollow cylinder 22, which can rotate, smoothlysliding around its geometrical axis. Said cyllnder carrles 1n lts turntwo parallel axles 23,24 both perpendicuf lar to the axis of thecylinder, and connected togetherby means of two small gears 25,26 andalittle chain 27 or by means of any other convenient system oftransmission.

On'the two axles 23,24 are also keyed two wheels 28,29 whose middleplanes are coincident. The wheel 28 has its peripherie surface closelycorrugated, the grooves being `parallel to the axle 23 the wheel 29 isindentical with the wheel 18.. A standard 30 fixed to the platform 2lsupports the horizontal wheel 31 which is identical to the wheel 28.Thus in each speed changing device there are provided two grooved wheels28, 31 and two wheels 18, 29 supplied with projecting pins.

The vcylinder and consequently the plane of the axles 23,24 is set inmotion by the geared crown wheel 32 applied in the middle to itsperiphery.

As pointed out above the rack 15 moves in proportion to the angle a, andby means of the gear 33 fixed to the platform 21, causes the cylinder 22to rotate in proportion to the angle a. The constants of the instrumentare chosen in such manner that when the vehicle deviates by the angle90a from the initial direction (which is assumed to be the -axis y), thecylinder will deviate from the initial position (that is to be that forwhich the plane of the axles 23,24 is horizontal) by the angle (Figs.6.4).

Therefore if the vehicle moves from A to A (Fig. 6) following thestraight line dS which forms with the axis the angle a, the

middle plane ofv the two wheels 28,29 will form constantly with thevertical the angle om dS the constant ,L being the factor ofproportionality.

In this displacement a pin of the wheel 18 entering in a groove of thewheel 28 parallel to the axis z, drags it along compelling it to turnaround its axle; the peripherie displacement of the wheel 28 will be-on-, being- 0nthe projection of 0m-- on the axis a. The displacement ofthe wl1cel29 willbe the same because the two wheels 28 and 29 are equal,parallel and mechanically connected,

One pin of the sprocket wheel 29 entering into a groove of thehorizontal wheel 31 drags it along in the same way as the couple 18,28and the displacement of the wheel 31 will be -opthe projection of ononthe axis w.

Therefore when the vehicle moves a distance d S, the wheel 29 will moveonly a distance op- (13) op= on sin (45 `lfVe will have But ` f om,aal/S' and d m= cos a d/S'. therefore op -d ,a being constant and wellknown it follows that the rotation of the wheel 31 will be proportionalto the displacement dm of the vehicle.

The same happens for the second speed changing device, the onlydifference being that the angle with the vertical of middle plane of thewheels 28 29 is because these planes form constantly an angle of 45 withthe middle plane of the wheels 28, 29

We will have then (o m being equal) and consequently being 0m=ydS{Z2/:Sen a dS n we will have Therefore when the vehicle moves from A toA the wheel 31 moves in proportion of dw and the wheel 31 moves inproportion of dy.

When the vehicle arrives in A and takes the new direction A B inclinedtothe precedent direction A A by an angle du, we can consider that itrotates on the point A without leaving its place; the cylinders 22,22rotate of the same angle 2l but as their e of speed and through thepoints of contact between 18.',28, 29,31 of the second speed changingdevice, the rotation of the cylinders does not produce any movement ofthe wheels 31 and 31', therefore the movement of the wheels 31,31 isonly proportional to the displacement of the vehicle along the axes andy respectively when it moves from A to A. i

On the axles of the wheels 31, 31 are keyed respectively the two gears32,32 (Fig. 8) which move the two orthogonal racks 33,33; the bar 33will move in proportion of dm and the bar 33 will move in proportion ofdy;

The two racks reproduce on the drawing sheet the axes m and y of theground; they carry two small bars of circular section 34,34', in theintersection of these is provided a pencil 35 which moves asl thevehicle and marks at every moment in the drawing sheet the position ofthe vehicle on the ground.

The instrument will find numerous applications in the fields oftopography, sports nautics, aereonautics and strategy, naturally if itis applied to a ship or to a dirigible it is necessary to substitute tothe wheels 1, 1 rolling on the ground, two screws at sea or in the air.Many ofthe mechanical connections described can be substituted by elecydesigned to trace on said sheet the course follow'ed by a vehicle, atransmission interposed between the writing point and two coaxial wheelsof the Vehicle which rotate independently the one from the other, bymea-ns of which transmission are imparted to the writing point twomovements at a time in the directionsl of two orthogonal axes traced onthe record sheet, each of said movements being proportional to thecorresponding instantaneous displacement of the vehicle lin respect oftwo fixed orthogonal axes intersecting in that point of the ground fromwhich the vehicle has started for its travel.

2. In an odograph as specified in claim 1, a device for imparting themovement to the writing point, consisting in two sliding bars, which canbe shifted in directions perpendicular to the directions of the fixedaxes traced on the record sheet, a connection between said bars and twowheels of the vehicle controlling their movement, said connectionintransmission, in such a manner that, when the vehicle moves along acurved path and the driving wheels perform a different number ofrotations, thereby causing thedifferential gear to come into action, thesaid differential gear acts on the speed changing device in such amanner that the ratios of transmission between each bar and thecorresponding wheel are automatically adjusted in proportion of thesines and cosines of the angle which the instantaneous direction of thevehicle forms with the initial direction.

3. In an odograph as specified in claim l, a device for effecting thetransformation of a rotation around an axis moving in a plane, andspecifically the rotation of the shafts of the satellite pinions of adifferential gear interposed between the driving wheels and the writingpoint, which shafts move in a plane perpendicular to the rear axle ofthe vehicle, in a rotation around a fixed axis.

4. In an odograph as specified in claim 1, with a differential gearbetween the driving wheels and the writing points, a device fortransforming the rotation of the shafts of the satellite pinions of thedifferential gear, which takes place in a plane perpendicular to therear axle of the vehicle, in a rotation around a fixed axis, consistinin a cage shiftable along the rear axle o the vehicle and comprising twoend covers connected bf; means of cross rods, two racks meshing Witgears mounted on the shafts of the satellite pinions of the differentialgear, said cage being mounted rotatable around the rear axle,

along which it can be shifted together with the system of satellitepinions, the two end covers sliding with their edges within two notchesof a 'rack slidinrr in turn longitudinally in guiding-pieces xed to thebodyl of the vehicle, which rackmeshes with a ear, the axle of which isalso fixed to the ody of the vehicle.

5. In an odograph as specified in claim 1, with a differential gearbetween the driving wheels and the writing point, a speed-changingdevice with variable transmission ratio interposed between the two halfaxles of the differential gear and the sliding bars which control themovement of the writing point consisting of two cylindrical trunksmounted rotatably in seats fixed to the body of the vehicle and bothcontrolled by a gear fixed to the body of the vehicle, each of saidtrunks,

including a sprocket wheel and a ribbed globular wheel with parallelaxles, both connected by a lconvenient transmission, the common plane-ofsaid two wheels being diversely orientated in the two trunks.

6. In an odograph as specified in claim 1, with a differential gear anda speed-changing device interposed between the driving wheels and thewriting point, the speed changing device comprising twoy rotatabletrunks, each including a sprocket wheel and a ribbed globular wheel,providing a sprocket wheel driven through a convenient transmission bythe corresponding half axle of the differential gear, and meshing withthe globular ribbed Wheel of one of the trunks, and a globular ribbedwheel connected by means of an appropriate transmission vwith one of thesliding bars of the writing point, and meshingl with the sprocket wheelof the same trunk.

In witness whereof I have signed my name to this specification at Rome,this 20th day of April, 1927. I

LUIGI KAMBo.

